1. Field of the Invention
The present invention relates to an apparatus for manufacturing an organic light-emitting diode (OLED) display and a method of manufacturing an OLED display using the apparatus, and more particularly, to an apparatus for manufacturing an OLED display in which an organic layer is formed on a substrate and a method of manufacturing an OLED display using the apparatus.
2. Description of the Related Art
Displays for displaying various information on the screen are core technology of the information and communications age and are evolving into thinner, lighter, portable, and high-performance displays. In particular, flat panel displays such as organic light-emitting diode (OLED) displays are drawing a lot of attention because they can overcome disadvantages of cathode ray tubes (CRTs), that is, reduce the weight and volume of the CRTs. An OLED is a self-emitting device that uses a thin organic light-emitting layer disposed between electrodes and can be made as thin as paper. OLED displays may be divided into small molecule OLED displays and polymer OLED displays according to the material of an organic light-emitting layer that generates light. An organic light-emitting layer of a small molecule OLED display is generally formed in the form of a thin film by vacuum deposition, and an organic light-emitting layer of a polymer OLED display is formed in the form of a thin film by a solution coating method such as spin coating or inkjet printing.
If inkjet printing is used to form an organic light-emitting layer, an inkjet print head may eject organic light-emitting ink which contains an organic light-emitting material and a solvent to at least one pixel on a display area of a substrate, and the ejected organic light-emitting ink may dry to form the organic light-emitting layer. Here, when the organic light-emitting ink dries, it may mean that the solvent contained in the organic light-emitting ink evaporates. Generally, a solvent is highly volatile. Therefore, the solvent may be volatilized soon after the ejection of the organic light-emitting ink, thereby drying the organic light-emitting ink. Here, due to a difference in drying time between a region coated first with the organic light-emitting ink and a region coated later with the organic light-emitting ink, the region coated first with the organic light-emitting ink and the region coated later with the organic light-emitting region may have different drying profiles. If the organic light-emitting layer disposed in pixels on the substrate has different drying profiles due to the difference in the drying time of the organic light-emitting ink, a thickness of the organic light-emitting layer may become non-uniform across all regions of the substrate. This can directly affect the display quality of an OLED display.